Combined copy paper pre-feed and timing mechanism for copying machines



J. F. MICIUKIEWICZ COMBINED COPY PAPER PRE-FEEDAND TIMING Sheets -Sheet1 June 30, 1970 MEQHANISM FOR COPYING MACHINES Filed May 21. 1968 vINVENTOR. JOSEPH F. MICIUKIEWICZ RM! 0 alum,

ATTORNE Y June 30, 1970 J. F. MICIUKIEWICZ 3,517,921

- COMBINED COPY PAPER FEE-FEED AND TIMING MECHANISM FOR COPYING MACHINES2 Sheets-Sheet 2 Filed May 21. 1968 INVENTOR. JOSEPH F. MICIUKIEWICZ J M12 aim AT TOR NE Y United States Patent Ofice 3,517,921 Patented June30, 1970 3,517,921 COMBINED COPY PAPER PRE-FEED AND TIMING MECHANISM FORCOPYING MACHINES Joseph F. Miciukiewicz, Trumbull, Conn., asslgnor toPitney-Bowes, Inc., Stamford, Conn., a corporation of Delaware Filed May21, 1968, Ser. No. 730,765 Int. Cl. G03b 27/48 US. Cl. 271-8 22 ClaimsABSTRACT OF THE DISCLOSURE A mechanism for use in a copying machine ofthe type utilizing precut sheets of copy paper in which the copy papersheets are stored in a supply tray and a sheet is normally maintained inan advanced or pre-fed position. The mechanism pre-feeds the topmostsheet from the supply tray to the advanced position preparatory to asubsequent copying cycle of operation, correlates the operation offeeding components for the copy paper according to varying length ofcopy paper and document for shortest possible copying time, and controlsthe operation of a lamp and charger during a current cycle of operationall under the control of switches actuated by the moving document andsheet of copy paper.

Background of the invention This invention relates generally toimprovements in feeding mechanism for copying machines and moreparticularly to a combined feeding mechanism and timing device for acopying machine utilizing copy paper in the form of cut sheets.

In copying machines of the type which utilize copy paper in cut sheetform as distinguished from roll form, the desirability has beenrecognized, as evidenced by US. =Pats. 3,345,926 and 3,352,281, ofpre-feeding of sheet of copy paper from a supply stack thereof to anadvance or ready position as the final step in a preceding cycle ofoperation of the copying machine, so that the sheet of copy paper hasadvanced a predetermined distance along a copy paper path prior to thenext copying operation.

The use of cut sheet copy paper is itself desirable in low cost copyingmachines since the need for a cutting mechanism as well as suitablecontrols for operating the cutting mechanism is eliminated. Also, cutsheet storage is more compact than roll paper storage, which isimportant in a relatively small desk top type copying machine. However,a major disadvantage in the use of cut sheet copy paper in most priorart copying machines is in the increased length of time required to makea single copy of an original document from the moment the documentisinserted into the copying machine until the finished copy isdelivered. The reason for this is that, in the design of the copier, itusually is not possible to locate the copy paper storage tray in aposition which places the leading edge of the stack of paper as close tothe copying components as is possible with a roll type copying machine,thereby increasing the length of the copy paper pattfi and the timerequired to move a sheet through the pa For example, in a machineutilizing roll paper, the roll can be stored in any desirable locationwith a web portion thereof leading to a cutting mechanism locatedimmediately adjacent the copying components, e.g. the charger in anelectrostatic type copying machine. In a cut sheet machine, however,design characteristics often require that the copy paper supply tray bedisposed adjacent an edge of the copying machine with the charger aconsiderable distance therefrom due to the configuration of the opticalsystem and the desirability of keeping the charger as close as possibleto the exposure area. Also, sufiicient space must be allocated betweenthe front edge of the supply tray and the charger for at least one pairof feed rollers which feed the sheet into the charger. Further, thedesign must provide for a level paper tray which is convenient foroperator access for loading.

A practical solution to the problem of the increased length of timerequired to obtain a copy from a cut sheet type copying machine, asagainst the shorter time required to make the same copy in a roll papertype machine, is to normally store a sheet of copy paper in an advancedor ready position with its leading edge disposed as close as possible tothe copying components of the machine. As shown in the above mentioned'U.S. patents, this is most desirably accomplished by providing meansfor separating and feeding the topmost sheet of the stack of copy paperfrom the stack storage location to the ready position as a final stepincident to a complete cycle of operation of the copying machine, or atleast as an intermediate step while a preceding copy is being developedand delivered to the machine operator. Thus the time required topre-feed the sheet of copy paper from the stack to the ready position isabsorbed in the normal time required to process the copy made on apreceding sheet of paper, and is not made cumulative with the normalprocessing time for making a copy.

The present invention is directed to improve means for feeding a sheetof copy paper from a stack thereof to an advanced or ready position inthe copying machine, and in this regard, constitutes an improvement onthe corresponding means of the above mentioned patents. It is known tocontrol the advance of a sheet of copy paper for a predetermineddistance only under the control of a plurality of paper actuatedswitches which in turn control the operation of electric motors and/orclutches to start and stop a plurality of paper feeding devicesaccording to a predetermined program. A major disadvantage of thisarrangement resides in the relatively large number of paper actuatedswitches which must be employed to control the stopping and starting ofthe copy paper feeding mechanism to move a sheet over the requireddistance. Paper actuated switches are not only expensive due to theirhigh degree of sensitivity, but also they are frequently a source oftrouble due to the possibility of causing paper jams. This latter aspectis particularly undesirable in the copy paper path where it requires aconsiderable amount of disassembly of the machine to clear a jammedsheet of paper. In general, the more that paper actuated switches can beeliminated, the greater is the degree of reliability of trouble freeoperation of the copying machine.

Brief summary of the invention there is provided a copying machinehaving a storage means for a stack of sheet of copy paper, a guiding andtransporting means defining a path of travel having an infeed endadjacent the storage means and extending through the copying machine,means for continuously driving the transporting means, and meansdefining an exposure zone spaced along the path of travel in which asheet of copy paper is exposed to an image of indicia on an originaldocument. In this combination the present invention is directed toward amechanism for successively feeding sheets of copy paper from the storagemeans to the guiding and transporting means and comprises a firstfeeding means disposed adjacent the storage means for feeding thetopmost sheet from the stack into the infeed end of the guiding means,and a second feeding means spaced along the path of travel between theinfeed end thereof and the exposure zone, the second feeding means,which is preferably a pair of intermittently driven feed rollers,defining an advanced position for the leading edge of a sheet of copypaper. A clutch means is provided for alternately connecting the drivingmeans to the first and second feeding means, the clutch means beingoperative to connect the driving means to the second feeding means atthe beginning of a copying cycle of operation of the copying machine andto the first feeding means after the trailing edge of the sheet haspassed the second feeding means. In order to control the movement of thesheet of copy paper there is provided means operatively associated withthe clutch means and with the first feeding means for limiting theoperation of the first feeding means, during the time that the clutchmeans is operative to conmeet the driving means to the first feedingmeans, to feed a sheet of paper from the storage means substantiallyonly a distance sufficient to bring the leading edge of the sheet intooperative engagement with the second feeding means, with the result thatthe sheet is moved from the storage means only to the advanced positionand not beyond preparatory to a subsequent copying cycle of operation ofthe copying machine.

A significant aspect of the present invention is the fact that theclutch means is responsive to operation of a control means in thecopying machine which may be either manually operated or may be operatedautomatically by sensing the leading and trailing edges of an originaldocument. Thus the present invention is applicable both to book copierswhere the original is merely placed on a platform for illumination and acopying cycle of the machine is initiated by a manual control, as wellas to strictly document copiers where the document is inserted into atransporting system and the document itself automatically initiates acopying cycle of operation of the machine.

As will be made more clear hereinafter, the simplicity and reliabilityof the device of the present invention resides in the fact that the leadedge of the copy paper sheet is engaged preferably in the nip of a pairof feed rollers which are driven by the clutch means in synchronism withthe main copy paper transport system only on demand as controlled by amanual or automatic control, these feed rollers becoming inoperative andthereby conditioned to receive the leading edge of the next sheet ofcopy paper as soon as the trailing edge of the previous sheet has passedby these feed rollers.

An advantageous feature of this invention resides in the fact that amechanical motion of the means limiting the operation of the firstfeeding means to a feed a sheet only to the advanced position isutilized to control the energization of an illuminating lamp and copypaper charger so that further elimination of paper actuated switches tocontrol these functions is achieved.

Having briefly described one embodiment of the present invention, it isa principal object thereof to provide a new and improved copy paperfeeding mechanism for copying machines.

It is another object of the present invention to provide a copy paperfeeding mechanism for copying machines which accurately pre-feeds asheet of copy paper from a paper storage position to an advanced orready position.

It is another object of the present invention to provide a copy paperfeeding mechanism for copying machines which pre-feeds a sheet of copypaper from a storage position to an advanced or ready position as anintermediate or terminal step in the cycle of operation of the copyingmachine during which a copy is being made on a previously fed sheet ofcopy paper.

It is still another object of the present invention to provide a copypaper feeding mechanism for a copying machine which is operable to bothadvance a sheet of copy paper from a ready position into the copy papertransport system and to pro-feed the next sheet of copy paper from astorage position to the ready position in response to operation ofeither a manual or automatic paper actuated control.

It is yet another object of the present invention to provide a copypaper feeding mechanism for a copying machine which is operable tocontrol the instant and duration of energization of an illuminating lampand copy paper charger without the necessity of any additional paperactuated switches.

A further object of the present invention is to provide a copy paperfeeding mechanism for a copying machine which has provision for sensingthe length of copy paper sheets and documents being copied and forcontrolling the sequence of operation of feeding components to delivercopy in the shortest possible time.

It is a further object of the present invention to provide a copy paperfeeding mechanism for a copying machine which is extremely simple indesign and construction, is highly reliable and accurate in operationand is economical to manufacture.

These and other objects and advantages of the present invention will bemore readily apparent from an understanding of the following detaileddescription of one embodiment of the present invention when consideredin conjunction with the accompanying drawings in which:

FIG. 1 is a logitudinal sectional view through a copying machineembodying the present invention;

FIG. 2 is a side elevation drawn to an enlarged scale of the copy paperfeeding mechanism of the present invention;

FIG. 3 is a side elevation of the one revolution drive element of themechanism shown in FIG. 2; and

FIG. 4 is a view taken on the line 44 of FIG. 3.

Detailed description Referring now to the drawings and particularly toFIG. 1 thereof, there is shown in diagrammatic form a copying machine 10of the second type above mentioned wherein an original document istransported through the machine and in which the present invention maybe utilized. Although a considerable amount of detail of constructionhas been omitted from FIG. 1 for the sake of clarity, which detaileither forms no part of the present inven tion or is obvious to anyoneskilled in the art to which the present invention relates, the figurenevertheless shows all of the major working components of anelectrostatic copying machine with sufficient particularity to obtain afull and complete understanding of the paper feeding mechanism of thepresent invention.

More particularly, there is provided a generally rectangular framecomprising a pair of upstanding parallel side plates 12 and 14 (plate 14being shown in FIG. 2) between which all of the interior components ofthe copying machine are mounted. Certain other components to be decribedhereinafter are mounted on the outside of plate 14, and in practice theentire frame is covered with a suitable housing having access openingsfor ingress and egress of documents to be copied and for egress ofcopies.

A plate 16 suitably supported by the frame plates 12 and 14 andassociated with an opening in the aforementioned housing defines aninlet guideway for original documents to be copied, and directs theleading edge of a document to the nip of pair of feed rollers 18 and 20rotatably supported by the plates 12 and 14. A pair of substantiallyvertical guide plates 22 and 24 define a portion of a document feed pathwhich extend downwardly along the front edge of the copying machine.Another pair of guide plates 26 and 28 define another portion of thedocument feed path which includes an illuminating station or Zonedefined by an elongate slit 30 formed in the guide plate 26. Adjacentthe lower end of the guide plates 26 and 28 is another pair of feedrollers 32 and 34 which direct the document between the curved guideplates 36 and 38 which in turn direct the document out of the copyingmachine. All of the foregoing elements together define a guiding andtransporting means for the original documents.

The pairs of feed rollers 18-20 and 32-34 are synchronously driven bymeans of a continuous moving drive chain 40, a portion of which is shownin FIG. 2. As will be more clear hereinafter, the chain 40 is driven bya suitable motor conveniently located in the copying machine, the chain40 passing around suitable sprockets and gears connected to a pluralityof sets of feed rollers. and also passing around suitable idlersprockets in order to drive the feed rollers synchronously in a mannerwell known in the art. Only the sets of feed rollers specificallymentioned below are not directly driven by the chain 40.

In order to project an image of indicia on an original document to asheet of copy paper for copying, an optical system is provided whichcomprises a source of illumination in the form of a lamp 42 and aprojecting shield 44 which concentrates the light from the lamp 42 onthe illuminating station defined by the slit 30 in the guide plate 26.Rays of light are reflected from a document passing by the slit 30 to amirror 46 which directs the rays of light through a focusing lens 48 toa reflex lens 50 having a reflecting surface 52. The rays of light arethen refiected back through the focusing lens 48 to anothermirror 54which directs the rays of light to an elongate slit 56 formed in a guideplate 58 which, together with a juxtaposed guide plate 60, defines anexposing station or zone for a sheet of copy paper which is fed betweenthe guide plates 58 and 60 by means hereinafter described.

It will be apparent to those skilled in the art that all of theforegoing elements of the optical system are suitably supported in thepositions shown in FIG. 1 by mountings or brackets which are connected,directly or indirectly, to the frame plates 12 and 14.

The guide plates 58 and 60 are part of a guiding and transporting meansdefining a path of travel through which sheets of copy paper are fedfrom a supply thereof through a charging device, the exposing station,and through a developing and drying station to a discharge locationaccessible to an operator. More particularly, a stack of copy paper 62is supported by a copy paper storage tray 64 which is pivotallysupported by a shaft 66 mounted in the frame plates 12 and 14. A spring68 connected at one end 70 to one of the frame plates and at the otherend 72 to the rear end of the copy paper tray 64 urges the tray 64 in aclockwise direction about the shaft 66. The tray 64 is provided with aside guide 74 along each side of the tray 64 which centers the stack 62of copy paper, and a corner separator 76 of known construction ismounted on the front corners of the tray 64 to assist in separating thetopmost sheet from the rest of the stack when the sheet is fed in amanner described hereinafter.

Positioned adjacent the front end of the paper supply tray 64 is a firstguide plate 78 and a second juxtaposed guide plate 80, the guide plates78 and 80 being suitably shaped so as to provide a relatively wideinfeed opening 81 into the copy paper path of travel and to define agradually restricted path which leads into a vertical portion to therebydirect the leading edge of a sheet of copy paper to the nip of a pair offeed rollers 82 and 84. This pair of feed rollers, which is a secondfeeding means of the invention as hereinafter more fully described,defines an advanced position to which a sheet of paper is initially fedfrom the storage tray 64.

Located downwardly from the feed rollers 82 and 84 is a corona dischargedevice 86 of known construction which imparts a uniform electrostaticcharge to the sheet of copy paper passing therethrough. A pair of feedrollers 88 and 90 feeds the sheet of copy paper from the exposingstation 56 into a developing tank 92 which contains a suitable toner fordeveloping the latent electrostatic image left on the copy paper afterit passes the exposing station 56. Suitable guide elements 94 and 96guide the sheet of copy paper through the toner tank 92 and direct theleading edge of the sheet to another pair of feeding rollers 98 and 100which also act as squeegee rollers to squeeze all excess toner off ofthe copy paper. A pair of juxtaposed guide plates 102 and 104 guide thesheet of paper through a drying zone and to a final pair of feed rollers106 and 108 which deliver the copy sheet to a receiving tray 110 inwhich the finished copy sheet is accessible to an operator through anopening 112 formed in the front of the housing.

Qoming now to the mechanism for successively feeding sheets of copypaper from the storage tray to the copy paper guiding and transportingmeans so that the leading edge thereof arrives at the exposing stationin synchronization with the arrival of the leading edge of an originaldocument at the illuminating station, and referring first to FIG. 1,there is shown a first feeding means comprising a shaft rotatablysupported by the side plates 12 and 14 in a position overlying theforward or feeding end of the paper storage tray 64. The shaft 120fixedly carries at least one feed roller 122 and preferably a pluralityof feed rollers which, when rotated by the shaft 120, feed the topmostsheet from the stack 62 into the infeed end of the copy paper pathhereinabove described. The shaft 120 carries a gear 124 located on theouter side of the frame plates '14 and therefore is shown in phantomlines in FIG. 1 and in solid lines in FIG. 2. Additional portions of thecopy paper feeding mechanism are also shown in phantom lines in FIG. 1for the sake of relating thelocation of the structure shown in FIG. 2 tothe rest of the copying machine shown in FIG. 1. The gear 124 isdrivingly connected to the shaft 120 by any suitable overriding or oneway drive means so that the shaft 120 and feed rollers 122 are driven ina clockwise direction as viewed in the figures when the gear 124 isdriven in the same direction, but the feed rollers 122 and shaft 120 canrotate in a clockwise direction independently of rotation of the gear124. Thus after the feed rollers 122 have fed the sheet a predetermineddistance to the advanced position defined by the feed rollers 82 and 84,the latter when actuated as hereinafter described, can pull theremainder of the sheet from the storage tray 64 without altering theposition of the gear 124 and other elements associated therewith asfully explained below.

Referring to FIG. 2, it will be seen that the chain 40', which it willbe recalled is continuously driven during the time that the copyingmachine is in an on conditions, passes around a floating idler sprocket126 which is urged downwardly by a tension spring 128 connected betweenthe idler sprocket shaft 130 and the frame plate 14, thereby maintainingproper tension on the chain 40. The chain also passes around and drivesa sprocket 132 rotatably carried by a stub shaft 134 mounted on theplate 14. A gear 136 is rigidly connected to the. sprocket 132 forrotation therewith.

In order to alternately connect the driving means to the first andsecond feeding means, there is provided a clutch means which, in thepreferred embodiment, comprises a lever 138 pivotally carried by thestub shaft 134 and having a tail portion 140 to which is connected aspring 142 which urges the lever 138 in a clockwise direction about thestub shaft 134 and normally maintains the tail portion 140 in contactwith an adjustable stop member 14 4. A solenoid 146 has its core 148connected to the lever 138 intermediate the shaft 134 and the tailportion 140 so that when the solenoid is energized the lever 138 ispivoted about the shaft 134 in a counterclockwise direction against therestoring force of the spring 142. Energization and deenergization ofthe solenoid 146 is controlled preferably by paper sensing switches in amanner described below.

The lever 13-8 rotatably carries a first gear 150 which meshes with thegear 136, and a second gear 152 which meshes with the gear 150 wherebyrotation of the gear 136 by the drive chain 40 also drives the gear 152.The gear 152 is adapted to mesh alternately with a gear 15-4 fixedlycarried by an extension of the shaft 156 on which the feed roller 84 ismounted, and another gear generally designated 158 rotatably carried bya stub shaft 160 mounted on the plate 14. Thus the lever 138, thesolenoid 146, the spring 142 and the gears 136, 150 and 152 allconstitute a paper actuated clutch means for alternately connecting thedrive chain 40 into driving engagement with the gear 154 or the gear158, the clutch means being in the former condition to drive the feedrollers 82 and 84 when the solenoid 146 is energized and being in thelatter condition to drive the gear 158 when the. solenoid 146 isdeenergized.

The gear 158 is actually an intermittently operable drive transferelement and forms part of a means for limiting operation of the feedrollers 122, even while, the clutch means is in its normal position toconnect the driving means to the feed rollers 122, to feed a sheet onlythe predetermined distance between the supply tray 64 and the advancedposition. In the preferred embodiment, this drive element is a partiallymutilated gear which is adapted to make one revolution in response toengagement therewith by the gear 152, after which the element 158 stopsturning until the gear 152 is released from engagement with the element158 by the clutch means and is reengaged therewith after a certainperiod of engagement with the gear 154. By operation of this element,the rollers 122 are efiective to pre-feed the topmost sheet of copypaper from the stack to a position where the lead edge of said sheet isin contact with the nip of the feed rollers 82 and 84, after which therollers 122 stop feeding even though the gear 152 of the clutch meansremains engaged with the drive transfer element 158.

More particularly, and referring to FIGS. 2-4, the element 158 comprisesa disc 162 having an annular rim 164 with teeth 166 formed thereon whichextend across the width of the rim 164. A recess 168 is formed in therim adjacent one side thereof, the recess extending across approximatelyone-half the width of the rim 164. The gear 152 is approximately thesame width or a little less than the depth of the recess 168 and ismounted on the lever 138 so as to be in alignment with the recess 168with the result that the teeth of the gear 152 do not mesh with theteeth 166 of the element 158 when the recess 168 is adjacent the gear152. Thus the gear 152 cannot drive the element 158 even though thesolenoid 146 is deenergized until the element 158 is rotated by othermeans to move the recess 168 away from the position shown in FIG. 2.

The element 158 is also provided with a semi-circular stud 170 whichprojects outwardly from the outer face of the element 158 as viewed inFIG. 2, the stud 170 making contact with a nose 172 formed on the end ofthe lever 138 to thereby prevent rotation of the element 158 until thelever 13-8 is rocked by energization of the solenoid 146. The element158 is also provided with a cam track 174 formed on the inner surface ofthe element 158, the cam track following a circular path adjacent therim 164 for most of the circumference of the cam track, but having asomewhat radially inwardly extending flat portion 176 disposed inangularly offset relationship with the recess 168 and terminating in acurved detent portion 177.

A spring loaded actuator in the form of a lever 178 is pivotally carriedby a stud 180 mounted on the frame plate 14, the lever 168 rotatablycarrying a cam follower roller 182 adjacent the cam track '174. Atension spring 8 184 connected between the opposite end of the lever 168and the frame plate 14 forcibly urges the lever in a clockwise directionabout the pivot st-ud 180 so as to maintain firm contact between theroller 182 and the cam track 174.

The operation of the drive transfer element 158 in conjunction with theclutch means described above is as follows: When the solenoid 146 isenergized by means described below, the lever 138 is rockedcounterclockwise about the stub shaft 134 to simultaneously move thenose 172 out of contact with the stud 170 on the element 158, and toengage the gear 152 with the gear 154, thereby driving the feed rollers82 and 84, since, it will be remembered, the chain 40, sprocket 182, andgears 136, and 152 are continuously rotating. As soon as the nose 172moves beyond the stud 170, the roller 182, bearing on the fiat 176 ofthe cam track 174, moves the gear 158 through a small angular distanceuntil the roller 182- comes to rest in the detent portion 177 butsufiicient to move the recess 168 away from its position adjacent theelement 152. This movement of the element 158 is caused by the upwardforce exerted on the flat portion 176 of the cam track 174 by the roller182 as a result of the strong pulling force of the spring 184 actingthrough the lever 178.

When the solenoid 146 is deenergized, the spring 142 returns the lever138 to the position shown in FIG. 2 whereupon the gear 152 is disengagedfrom the gear 154 and is engaged in driving relationship with the teeth166 of the drive transfer element 158 to rotate the latter. Rotation ofthe element 158 rotates the gear 124 which rotates the shaft 120 throughthe one way drive means mentioned above which in turn rotates the feedrollers 122. This continues until the recess 168 again comes around to aposition adjacent the gear 152 at which point the gear 152 ceases tohave driving engagement with the element 158, and the stud is again inengagement with the nose 172 of the lever 138. Also, during rotation ofthe element 158 the cam follower roller 182 has been following thecircular portion of the cam track 174. The location of the recess 168and the fiat portion 176 just before the teeth of the gear 162 disengagefrom the teeth 166 of the element 158 so that the roller 182 moves ashort distance along the flat portion 176 of the cam track. This is toassure that the roller 182 will maintain the stud 170 in engagement withthe nose 172 of the lever 138 so as to properly position the recess 168adjacent the gear 152 and prevent any binding or scraping of the teethof the gear 152 and the element 158 when the latter is in its staticcondition. Thus it will be seen that the element 158 makes one completerevolution each time the solenoid 146 is energized and deenergized. Therelative diameters of the element 158 and gear 124, and the feed rollers122, are selected so that the topmost sheet of copy paper is fed adistance sufiicient to move the lead edge of the sheet from its normalposition in the stack to a position of engagement with the nip of thefeed rollers 82 and 84 during the same one revolution of the element158.

In order to relate the operation of the above described clutch mechanismand the first and second copy paper feeding means to the overalloperation of the copying machine 10, reference will now be made toFIG. 1. It will be seen that a control means in the form of a switch islocated adjacent the entrance to the original document path, the switch190 having a paper sensing actuator 192 disposed in the document path.The actuator 192 is located upstream from the illuminating area 30 adistance approximately equal to the distance between the exposing area56 and the nip of the feed rollers 82 and 84 in order to assure that theleading edges of the original document and the copy paper arrive at theilluminating and exposing areas respectively at the same time.

The switch 190 controls the energization of the solenoid 146 to energizethe latter in response to operation of the switch 190 by the leadingedge of a document and to deenergize the solenoid in response tooperation of the switch 190 by the trailing edge of the document.Assuming that the document is the same length as the copy paper storedin the machine, it will be understood that the trailing edge of thedocument will actuate the switch 190 to deenergize the solenoid 146 atabout the same instant that the trailing edge of the sheet of copy paperleaves the nip of the rollers 82 and 84. A second switch 194 is locatedin the copy paper path adjacent the feed rollers 82 and 84 and has apaper sensing actuator 196 disposed'in the paper path. This switch isconnected to the solenoid 146 in parallel with the switch 190 in orderto assure that the copy paper feed mechanism will run a full normalcycle of operation even if an original document is inserted into themachine which is shorter than the length of copy paper in the stack 62,since the copy paper feeding mechanism is intended to feed a standardsize sheet of paper. Also, the switches 190 and 194 combine in functionto control the operation of the clutch means and hence the first andsecond feeding means to deliver a copy in the shortest possible time.This is particularly so when making multiple copies or successivecopies.

A significant feature of the present invention is the utilization of themotion of the drive transfer element 158 to control the energization anddeenergization of the lamp 42 and the charger 86 in synchronism with theinitiation of a copying cycle of operation and with passage of thetrailing edge of a document and a sheet of copy paper through theilluminating and exposing areas respectively. Thus, a third switch 198(FIG. 2) is mounted on the plate 14 and has an actuator finger 200extending toward the element 158 and lying in a position to bealternately moved and released by a stud 202 which projects from therear face of the element 158 in axial alignment with the stud 170*projecting from the front face of the element 158. The actuator finger200 terminates at the stud 202 so that it is released for movement awayfrom the switch 198 as soon as the element 158 is rotated the smallangular movement by the roller 182 and the spring loaded lever 168. Thismovement of the actuator finger 200 closes the switch 198 which closessuitable circuits to energize the illuminating lamp 42 and the copypaper charger 86. The switch 198 remains closed until the element 158completes its copy paper driving movement after the solenoid 146 isdeenergized and returns to the position shown in FIG. 2, whereupon thestud 202 again engages the actuator finger 200 to open the switch 198,thereby turning off the lamp and charger. Thus it will be seen that theelement 158 which controls the copy paper pre-feed function alsofunctions as a timing device to control the moment and duration ofenergization of the lamp and charger during a normal copying cycle ofthe machine, and assurs that the lamp and charger will remain energizeduntil the document and copy paper have cleared their respectiveilluminating and exposing areas.

A complete cycle of operation of the copying machine will now bedescribed with reference to the drawings. An original document is placedon the shelf 16 from which it slides into the nip of the feed rollers 18and 20. After being picked up by the feed rollers, the leading edge ofthe document closes the switch 190 which energizes the solenoid 146 toshift the clutch mechanism into driving engagement with the gear 154.The rollers 82 and 84 then begin to feed the sheet of copy paper whichhas been pre-fed to the advanced position where the leading edge of thesheet is engaged in the nip of the rollers 82 and 84 during the previouscycle of operation of the machine 10.

As soon as the clutch mechanism shifts, the drive transfer element 158rotates slightly so that the stud 202 releases the actuator finger 200whereupon the switch 198 turns on the lamp 42 and the charger 86. Theoriginal document and the sheet of copy paper advance in syn chronismthrough their respective paths, the copy paper first passing through thecharger 86 and then through the exposing area while the document isapproaching and passing through the illuminating area. When the feedrollers 82 and 84 initially feed the copy paper sheet, the trailing endportion of {the sheet which is still overlying the stack pulls the feedrollers 122 in the feeding direction by virtue of the one way driveconnection between the gear 124 and the shaft 120.

The clutch mechanism is held in driving engagement with the gear 154until the trailing end of the document actuates the switch 190 or thetrailing end of the copy paper sheet actuates the switch 194, whicheveroccurs later, at which time the solenoid 146 is deenergized and theclutch mechanism shifts back to its spring loaded position. The gear 152then drives the element 158 through one revolution in the mannerexplained above, during which time the gear 124, the one way drivemeans, the shaft and the rollers 122 feed the next sheet of copy paperinto the copy paper path until the leading edge thereof is in the nip ofthe feed rollers 82 and 84. At this point the stud 202 will again engagethe actuator finger 200 to c1ose the switch 198 to turn off the lamp andcharger, but by this time the trailing edges of both the document andthe sheet of copy paper have cleared their respective illuminating andexposing areas. The original document is directed out of the machine bythe guide plates 36 and 38 while the exposed copy sheet continuesthrough the toner tank 92 for developing and is directed to thedischarge receiving tray 110. The copying machine is ready for anothercopying cycle of operation as soon as the element 158 has completed onerevolution and returned to its home position which condition may beconveniently indicated by an indicator light suitably wired throughother contacts of the switch 198.

As a practical matter, the dimensions of the feed rollers 122 anddriving gear 124 are selected so that in the course of one revolution ofthe drive transfer element 158, the rollers 122 feed a greater length ofa sheet of copy paper than is necessary to bring the leading edgethereof to the nip of the feed rollers 82 and 84. The reason for this isto create a bend or curved buckle in the sheet in the area of theentrance opening 81 to the copy paper path so as to assure that theleading edge of the sheet will not be skewed when it is fed into thecharger 86, and finally so that the sheet remains in the proper advancedposition for long periods of time if necessary to await the next copyingcycle of operation of the copying machine.

It has been indicated briefly above that the present invention hasapplicability to a book-type copying machine as well as to a sheet-typemachine. In the specific embodiment of the copying machine describedabove and shown in the accompanying drawings, it will now be recognizedthat the switch may be replaced by a manually operable start switchwhich is actuated after a book or any fiat document has been placed inposition on the illuminating component of the machine. This may be astationary transparent platform beneath which a traveling light sourcescans the book or document, or the platform may travel back and forthrelative to a stationary light source, both of which arrangements arewell known in the art.

When the equivalent start switch 190 is actuated manually, the samesequence of operation of the copy paper feeding mechanism takes place asfuly described above, with the exception that it is now necessary tohave the switch 194 in the copy paper path to keep the solenoid 146energized for the proper length of time since the start switch would beonly momentarily closed to energize the solenoid 146 and cause the feedrollers 82 and 84 to feed the sheet far enough to close the switch 194.Alternatively a secondary control for the solenoid 146 may be associatedwith the mechanical movement either of the document platform or the lampas the case may be.

It is now apparent from the foregoing that there has been provided acombined copy-paper pre-feed and timing mechanism for copying machineswhich avoids the disadvantages of prior art copying machines and whichachieves the foregoing objects. It is to be understood that the presentinvention is not intended to be limited to the specific embodimentdescribed above and shown in the accompanying drawings, which is merelyillustrative of the principles of the invention and is the best modepresently contemplated for carrying out the invention, and issusceptible to change in form, size, detail and arrangement of parts,the invention being intended to cover all such equivalents, variationsand modifications thereof as may be deemed to be within the scope of theclaims appended hereto.

I claim:

1. In a copying machine having storage means for a stack of sheets ofcopy paper, guiding and transporting means defining a path of travel forsheets of copy paper having an infeed end adjacent said storage meansand extending through the copying machine, means for continuouslydriving said transporting means, and means defining an exposure zonespaced along said path of travel in which a sheet of copy paper isexposed to an image of indicia on an original document, the combinationtherewith of a mechanism for successively feeding sheets of copy paperfrom said storage means to said guiding and transporting means, saidmechanism comprising (A) first feeding means disposed adjacent saidstorage means for feeding the topmost sheet from said stack into saidinfeed end of said guiding means,

(B) second feeding means spaced along said path of travel intermediatesaid infeed end thereof and said exposure zone, said second feedingmeans defining an advanced position for the leading edge of a sheet ofpy P p (C) clutch means for alternately connecting said driving means tosaid first and second feeding means and being operative to connect saiddriving means to said second feeding means at the beginning of a copyingcycle of operation of the copying machine and to said first feedingmeans after the trailing edge of a sheet has passed said second feedingmeans, and

(D) means operatively associated with said clutch means and said firstfeeding means for limiting the operation of said first feeding means,while said clutch means is operative to connect said driving means tosaid first feedingmeans, to feed a sheet of paper from said storagemeans substantially only a distance sufficient to bring the leading edgeof said sheet into operative engagement with said second feeding meanswhereby said sheet is moved from said storage means to said advancedposition preparatory to a subsequent copying cycle of operation of thecopying machine.

2. A combination according to claim 1 wherein said means limiting theoperation of said first feeding means comprises an intermittentlyoperable drive transfer element coacting between said clutch means andsaid first feeding means and having means for automatically disengagingsaid driving means from said first feeding means without disengagingsaid clutch means from said drive transfer element when the leading edgeof said sheet has been moved to said advanced position.

3. A combination according to claim 2 wherein said means for limitingthe operation of said first feeding means further comprises a yieldablemeans operable upon disengagement of said clutch means from said drivetransfer element to move said drive transfer element to a position wheresaid driving means is reengaged with said first feeding means uponreengagement of said clutch means with said drive transfer elementwhereby said first feeding means is operated sbsequent to said secondfeeding means during a cycle of operation of said copying machine.

4. A combination according to claim 2 wherein said first feeding meansincludes one way drive means coacting with said drive transfer elementwhereby said second feeding means can withdraw the remainder of a sheetof paper from said storage means without altering the position of saiddrive transfer element.

5. In a copying machine having storage means for a stack of sheets ofcopy paper, guiding and transporting means defining a path of travel forsheets of copy paper having an infeed end adjacent said storage meansand extending through the copying machine, means for continuouslydriving said transporting means, and means defining an exposure zonespaced along said path of travel in which a sheet of copy paper isexposed to an image of indicia on an original document, the combinationtherewith of a mechanism for successively feeding sheets of copy paperfrom said storage means to said guiding and transporting means, saidmechanism comprising (A) first feeding means disposed adjacent saidstorage means for feeding the topmost sheet from said stack into saidinfeed end of said guiding means,

(B) second feeding means spaced along said path of travel intermediatesaid infeed end thereof and said exposure zone, said second feedingmeans defining an advanced position for the leading edge of a sheet ofPY p p (C) control means in said copying machine for initiating acopying cycle of operation and for sensing when the trailing edge of asheet of copy paper has passed said second feeding means,

(D) clutch means responsive to said control means for alternatelyconnecting said driving means to said first and second feeding means,said clutch means being responsive to operation of said control meanswhen initiating a copying cycle of operation to connect said drivingmeans to said second feeding means and being responsive to operation ofsaid control means when sensing the movement of the trailing edge of asheet past said second feeding means to connect said driving means tosaid first feeding means, and

(E) means operatively associated with said clutch means and said firstfeeding means for limiting the operation of said first feeding means,while said clutch means is operative to connect said driving means tosaid first feeding means, to feed a sheet of paper from said storagemeans substantially only a distance sutlicient to bring the leading edgeof said sheet into operative engagement with said second feeding meanswhereby said sheet is moved from said storage means to said advancedposition preparatory to a subsequent copying cycle of operation of thecopying machine.

=6. A combination according to claim 5 wherein said means limiting theoperation of said first feeding means comprises an intermittentlyoperable drive transfer element coacting between said clutch means andsaid first feeding means and having means for automatically disengagingsaid driving means from said first feeding means independently ofoperation of said control means when the leading edge of said sheet hasbeen moved to said advanced position.

7. A combination according to claim 6 wherein said drive transferelement comprises a one revolution rotary drive member engaged betweensaid clutch means and said first feeding means, said drive member havingmeans for effecting a driving engagement between said clutch means andsaid first feeding means disposed over only a major portion of theperiphery of said drive member and having a minor portion of saidperiphery formed to interrupt said driving engagement.

8. A combination according to claim 7 wherein said drive member is agear having circumferential teeth which mesh with the teeth of a geardefining the output of said clutch means and another gear connected tosaid first feeding means, said drive member gear having an arcuaterecess in the teeth thereof which extends axially over a portion of thelength of said teeth, the teeth of said clutch output gear being nolonger than the depth of said recess in said drive member gear and beingaligned with said recess whereby said clutch output gear stops drivingsaid drive member gear when said recess registers with said clutchoutput gear.

9. A combination according to claim 8 wherein said drive member gearincludes stop means adapted to engage a poriton of said clutch meanswhen the'latter is engaged with said drive member gear, said stop meansbeing spaced in relation to said recess to positivelyar'rest movement ofsaid drive member gear when said recess registers with said clutchoutput gear.

10. A combination according to claim 6 wherein said means for limitingthe operation of said first feeding means further comprises a springloaded actuator operable in response to operation of said control meanswhen initiating a cycle of operation of the copying machine to move saiddrive transfer element to a position where said driving means isreengaged with said first feeding means when said control means operatesupon sensing the movement of the trailing edge of the sheet of copypaper past said second feeding means whereby said first feeding means isoperated subsequent to said second feeding means during a copying cycleof operation of said copying machine.

11. A combination according to claim 10 wherein said drive transferelement comprises a one revolution rotary drive member engaged betweensaid clutch means and said first feeding means, said drive member havingmeans for effecting a driving engagement between said clutch meansdisposed over only a major portion of the periphery of said drive memberand having a minor portion of said periphery formed to interrupt saiddriving engagement, said drive member further having cam meanscooperating with said spring loaded actuator for moving said drivemember only a distance sufiicient to dispose said minor portion of theperiphery of said drive member out of op erative association with saidclutch means.

12. A combination according to claim 11 wherein said drive member is agear having circumferential teeth which mesh with the teeth of a geardefining the output of said clutch means and another gear connected tosaid first feeding means, said drive member gear having an arcuaterecess in the teeth thereof which extends axially over a portion of thelength of said teeth, the teeth of said clutch output gear being nolonger than the depth of said recess in said drive member gear and beingaligned with said recess, said cam means having a portion aligned withsaid recess for moving said gear to a position where said recess isdisposed away from said clutch output gear whereby said clutch outputgear stops driving said drive member gear when said recess registerswith said clutch output gear and said recess is moved out ofregistration with said clutch output gear when said clutch means isagain engaged with said second feeding means.

13. A combination according to claim 12 wherein said drive member gearincludes stop means adapted to engage a portion of said clutch meanswhen the latter is engaged with said drive member gear, said stop meansbeing spaced in relation to said recess and to said portion of said cammeans aligned with said recess to positively arrest movement of saiddrive member gear when said recess registers with said clutch outputgear and to prevent said spring loaded actuator from moving said drivemember gear while said clutch output gear is engaged with said recess ofsaid drive member gear.

14. In a copying machine having storage means for a stack of sheets ofcopy paper, first guiding and transport ing means defining a first pathof travel for sheets of copy paper having an infeed end adjacent saidstorage means and extending through the copying machine, second guidingand transporting means defining a second path of travel for originaldocuments through the copying machine, means for continuously drivingsaid first and second transporting means in synchronism, and meansdefining an exposing zone and an illuminating zone spaced along saidfirst and second paths of travel respectively in which a sheet of copypaper is exposed to an image of indicia on an original document, thecombination therewith of a mechanism for successively feeding sheets ofcopy paper from said storage means to said first guiding andtransporting means, said mechanism comprising (A) first feeding meansdisposed adjacent said stor age means for feeding the topmost sheet fromsaid stack into said infeed end of said first guiding means,

(B) second feeding means spaced along said first path of travelintermediate said infeed end thereof and said exposure zone, said secondfeeding means defining an advanced position for the leading edge of asheet of copy paper.

(C) control means including sensing means located in said second path oftravel and spaced from said illuminating zone a distance substantiallyequal to the distance between said second feeding means and saidexposure zone in said first path of travel, said sensing means beingoperative to sense the leading edge of a document to actuate saidcontrol means to initiate a copying cycle of operation of the copyingmachine and operative to sense the passage of the trailing edge of thedocument,

(D) clutch means responsive to said control means for alternatelyconnecting said driving means to said first and second feeding means,said clutch means being responsive to operation of said control meansupon sensing the leading edge of a document to connect said drivingmeans to said second feeding means and being responsive to operation ofsaid control means upon sensing the trailing edge of a document toconnect said driving means to said first feeding means, and

(E) means operative associated with said clutch means and said firstfeeding means for limiting the operation of said first feeding means,while said clutch means is operative to connect said driving means tosaid first feeding means, to feed a sheet of paper from said storagemeans substantially only a distance sufficient to bring the leading edgeof said sheet into operative engagement with said second feeding meanswhereby said sheet is moved from said storage means to said advancedposition preparatory to a subsequent copying cycle of operation of thecopying machine.

15. A combination according ot claim 14 wherein said control meansincludes additional sensing means located in said first path of traveladjacent said second feeding means and operative to sense the passage ofthe trailing edge of a sheet of copy paper past said second feedingmeans, both said sensing means being operatively connected in saidcontrol means to cause the latter to maintain said clutch means engagedwith said second feeding means until the trailing edge of both thedocument and the copy paper sheet have passed the sensing means locatedin their respective paths of travel.

16. In a copying machine having a storage means for a stack of sheets ofcopy paper, guiding and transporting means defining a path of travel forsheets of copy paper having an infeed end adjacent said storage meansand extending through the copying machine and having an exposure zonespaced therealong from said storage means, \means for continuouslydriving said transporting means and means including a source ofillumination for projecting at image of indicia on an original documentto said exposing zone While a sheet of copy paper is passingtherethrough, the combination therewith of a mechanism for successivelyfeeding sheets of paper from said storage means to said transportingmeans and for controlling the energization of said illuminating means,said mechanism comprising (A) first feeding means disposed adjacent saidstorage means for feeding the topmost sheet from said stack into saidinfeed end of said guiding means, (B) second feeding means spaced alongsaid path of travel intermediate said infeed end thereof and saidexposure zone, said second feeding means defining an advanced positionfor the leading edge of a sheet of copy paper,

(C) control means in said copying machine for initiating a copying cycleof operation and for sensing when the trailing edge of a sheet of copypaper has passed said second feeding means,

(D) clutch means responsive to said control means for alternatelyconnecting said driving means to said first and second feeding means,said clutch means being responsive to operation of said control meanswhen initiating a copying cycle of operation to connect said drivingmeans to said second feeding means and being responsive to operation ofsaid control means when sensing the passage of the trailing edge of asheet past said second feeding means to connect said driving means tosaid first feeding means, and

(E) means operatively associated with said clutch means and said firstfeeding means for sequentially energizing said illuminating means whensaid clutch means is operated by said control means to connect saiddriving means to said second feeding means at the initiation of acopying cycle of operation and thereafter for simultaneously limitingthe operation of said first feeding means, while said clutch means isoperative to connect said driving means to said first feeding means, tofeed a sheet of paper from said storage means substantially only adistance sufficient to bring the leading edge of said sheet intooperative engagement with said second feeding means and for deenergizingsaid illuminating means substantially at the completion of saidoperation of said first feeding means whereby said sheet is moved fromsaid storage means to said advanced position preparatory to a subsequentcopying cycle of operation of the copying machine and said illuminatingmeans is maintained energized during said movement of said sheet.

17. A combination according to claim 16 wherein said last named meanscomprises a switch connected to said illuminating means, and anintermittently operable drive transfer element coacting between saidclutch means and said first feeding means and havingmeans forautomatically disengaging said driving means from said first feedingmeans independently of said control means when the leading edge of saidsheet has been moved to said advanced position, said drive element alsohaving means for closing said switch to energize said illuminating meanswhen said clutch means is engaged with said second feeding means and foropening said switch, to deenergize said illuminating means when saiddrive element disengages said driving means from said first feedingmeans.

18. A combination according to claim 17 wherein said last named meansfurther comprises a spring loaded actuator operable in response tooperation of said control means when initiating a copying cycle ofoperation of the copying machine to move said drive transfer element toa position where said driving means is reengaged with said first feedingmeans when said control means is operated upon sensing the movement ofthe trailing edge of a sheet of copy paper past said second feedingmeans, said drive transfer element including abutment means operativelyassociated with said switch for closing said switch upon movement ofsaid drive transfer element by said spring loaded actuator and foropening said switch at the completion of operation of said drivetransfer element when said first feeding means is disengaged from saidclutch means by said drive transfer element.

19. A sheet feeding mechanism for successively prefeeding sheets ofpaper from a supply stack to an advanced position and beyond comprising(A) supply means for a stack of sheets of paper disposed at a firstlocation,

(B) first feeding means operable to feed the topmost sheet from saidstack,

(C) second feeding means disposed at a second location spaced from saidfirst feeding means and adapted to receive a sheet from said firstfeeding means and to feed said sheet through said second feeding means,

(D) intermittently operable driving means connected to said firstfeeding means and operable when actuated to operate said first feedingto feed a sheet from said first location substantially only to saidsecond location for operative engagement with the leading edge of saidsheet by said second feeding means, and

(E) continuously operating shiftable driving means for alterntelydriving said first and second feeding means, said continuously operatingdriving means including (1) means under manual control for initiallyshifting said continuously operating driving means into engagement withsaid second feeding means, (2) sensing means for sensing when thetrailing edge of a sheet has passed said second feeding means, and (3)means responsive to operation of said sensing means by the trailing edgeof said sheet for shifting said continuously operating driving meansfrom said second feeding means into driving engagement with saidintermittently operable driving means, whereby a subsequent sheet is fedfrom said first location to said second location immediately upon apreceding sheet being fed beyond said second location.

20. A mechanism according to claim 19 wherein said intermittentlyoperable driving means comprises a drive transfer element having meansfor discontinuing driving operation of said drive transfer element aftera predetermined amount of operation thereof and while said continuouslyoperating driving means is engaged with said drive transfer element, andyieldable means responsive to operation of said manual control forresetting said drive transfer element to a position Where saidcontinuously operating driving means is drivingly engaged with saiddrive transfer element when said continuously operating driving means isshifted in response to operation of said sensing means by the trailingedge of a sheet.

21. A mechanism as set forth in claim 20 wherein said drive transferelement comprises a gear having circumferential teeth which mesh withthe teeth of. a second gear which is part of said continuously operatingdriving means and with a third gear connected to said first feedingmeans, an arcuate portion of the teeth of said drive transfer gear beingcut away over a portion of the axial length of said gear to define arecess, said second gear being in alignment only with the recessedportion of said drive transfer gear whereby said drive transfer gearstops operating when said recess therein registers with said secondgear.

22. A mechanism according to claim 21 wherein said gear includes cammeans cooperating with said yieldable means for moving said gear adistance sufficient to move said recess away from a position ofregistration with said second gear when said second gear is shifted tosaid second feeding means in response to said manual control.

References Cited UNITED STATES PATENTS 3,137,495 6/1964 Eichom 271-63,152,532 10/1964 Limberger 355--l07 EVON C. BLUNK, Primary Examiner D.D. WATTS, Assistant, Examiner

